Motor neurone disease sufferer Diane Pretty launches the latest stage of her "right-to-die" fight at the European Court of Human Rights in Strasbourg on Tuesday.

The BBC's Jon Silverman explains how the court works - and what the Prettys can expect.

What powers does the European Court of Human Rights have? Are its decisions binding on UK law?

All final judgments of the European Court of Human Rights are binding on the State involved. In other words, it is expected to change the law to accommodate the ruling.

Responsibility for ensuring that the member state complies with the judgement rests with the Committee of Ministers of the Council of Europe.

How does one take a case to the European Court? Can one go directly, or does one have to go through all the stages of domestic law first? If that is the case what are the stages that one must have to go through?

A case cannot be taken directly to Strasbourg without exhausting all possible legal remedies" at home" - it must have gone through the various tiers of court procedure, up to and including the House of Lords.

The Pretty case has been heard at the High Court, the Court of Appeal and finally, by the House of Lords.

Who presides at the European Court?

There are various stages - both written and oral - to determine admissibility but a hearing at the Grand Chamber of the European Court is before 17 judges.

Judgement is on a majority vote.

Is there any right of appeal once the European Court has handed down a decision?